Weak memory cells are memory cells that malfunction when operating at a lower voltage than a primary source voltage. In general, the malfunctioning manifests as an error when a bit value is incorrectly written to or read from the weak memory cell. The memory cells are “weak” in comparison to other memory cells that function properly at the same low voltage. In general, defects in the weak cells caused by process variations lead to malfunctions when a source voltage is lowered. Consequently, the presence of weak memory cells causes difficulties when operating in various modes (e.g., power saving modes) that use lower voltages.
Additionally, identifying which memory cells are weak cells can be a difficult task. For example, testing a memory for weak memory cells may include executing test data through the memory cells while lowering a voltage of the memory. However, because lowering the voltage also lowers a voltage of built-in testing components, the testing components may fail prior to detecting the weak cells. Furthermore, write and read errors merge together in output from memory cells because the operations occur in series prior to availability of an output. Thus, identifying weak memory cells and which operation is responsible for an error is difficult.